Results 211 to 220 of about 18,969 (256)

Modeling and Measurement of Complex Permittivity of Soils in UHF

IEEE Geoscience and Remote Sensing Letters, 2020
The complex permittivity of different types of soils in the ultrahigh frequency (UHF) is studied in this letter. A new model, whose inputs are the low-frequency conductivity and the volumetric water content, is proposed to estimate the complex permittivity of soils in UHF.
John J. Pantoja, Sergio Gutierrez, Edwin Pineda, David Martinez, Christoph Baer, Félix Vega   +5 more
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The theories of complex permittivity

Journal of Physics C: Solid State Physics, 1972
It is shown that the spectral density used by Scaife (1971) in his theory of complex permittivity is closely related to the autocorrelation function used by other authors and that both Scaife's equation and the equation in terms of autocorrelation functions follow immediately from the superposition principle.
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Measurement of complex permittivity and complex permeability of materials

12th International Conference on Microwaves and Radar. MIKON-98. Conference Proceedings (IEEE Cat. No.98EX195), 2002
The time domain measurement of complex permittivity and complex permeability in the 8 to 18 GHz frequency band is considered. Some methods for determination of permittivity and permeability are presented.
H. Alenkowicz, B. Levitas
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Measurement of Complex Permittivity and Permeability

1970
Abstract : The program was conducted to derive a better technique for the measurement of the permeability and permittivity of lossy ferrites at microwave frequencies at temperatures up to 1000F. Although the classical method of waveguide measurement techniques was used, a careful analysis of the sources of errors was undertaken and a computer aided ...
Eva M. Thomas, Abdelnour S. Thomas
openaire   +1 more source

The complex permittivity of human tissue at microwave frequencies

Physics in Medicine and Biology, 1982
The complex permittivity, and hence the emissivity, of the body, and the attenuation coefficient of skin were determined from simple measurements made on living human tissue over the frequency range 8 to 18 GHz.
G L, Hey-Shipton, P A, Matthews, J, McStay   +2 more
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A modified calibration method for complex permittivity measurement

Review of Scientific Instruments, 2013
This work proposes a calibration method to determine the complex permittivity of materials based on the cavity-perturbation method. The method can characterize a sample with relative large in volume or high in dielectric constant, which significantly broadens the scope of the conventional perturbation method.
Hsein-Win, Chao, Tsun-Hsu, Chang
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Non-Destructive Measurement of Complex Permittivity for Dielectric Slabs

4th European Microwave Conference, 1974, 1974
A method has been developed for a precise non-destructive measurement of the dielectric constant and losses of slab-like samples, such as microstrip substrates for instance. The test setup basically consists of an open-ended rectangular waveguide whose flange is placed in contact with one side of the dielectric material, the other one being backed by a
Decréton, M., Andriamiharisoa, V.
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The Complex Permittivity of Polyethylene/Mica Composites

IEEE Transactions on Electrical Insulation, 1982
The complex relative permittivity ?*(f) of polyethylene/mica composites has been measured in the frequency range 10-2 to 107 Hz, as a function of mica content ?2 and prior sample conditioning. ?*(f) was found to display two main features: ?'-?' ?and K'' vary as fn-1 with 0.64?n?0.83 for all ?2, on account of the intrinsic dispersive properties of the ...
L. Paquin, H. St-Onge, M. R. Wertheimer
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Microwave complex permeability and permittivity of nanoferrites

Journal of Applied Physics, 2011
Complex permittivity and permeability of nanosized magnetic powders are studied for eight different bands to cover the frequency range from 2–40 GHz. A precise transmission-reflection based waveguide technique has been used to carry out measurements across the frequency bands. The algorithm for transmission and reflection calculations has been modified
Anjali Sharma, Mohammed N. Afsar
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Measurement of complex permittivity of liquids. II

Journal of Physics E: Scientific Instruments, 1974
Improvements on the method of Lovell and Cole (1959) for the measurement of complex permittivity of liquids by means of the Boonton R-X Meter are presented. A new approach to the calibration of the cell and connecting line, considering ohmic losses, is described.
N L Federigi, G H Barbenza
openaire   +1 more source